A characterization of discrete solar wind events detected by interplanetary scintillation mapping

We examine the large-scale solar wind density and velocity characteristics which are associated with interplanetary disturbances detected by interplanetary scintillation (IPS) mapping. Our aim here is to characterize these remotely sensed events in order to provide a better foundation on which to consider both the origin of such phenomena and their influence on the near-Earth environment. We select those events from a list published by Hewish and Bravo (1986) that appear to be Earth crossing and consider the average density and velocity in the solar wind at the time. We find density (and often velocity) enhancements in association with the majority of these IPS events, though the changes are modest. Postevent conditions commonly show a slight velocity increase and density decrease with respect to preevent conditions.